Heavy snow in parts of the Midwest could cause as much as 100 million bushels of the 2009 corn crop to be lost. According to analysts in several Corn Belt states, a significant number of acres were yet to be harvested when snow came in December. Now, with the storm that struck the first week of January adding more snow, a lot of the corn still in the field will be there for the rest of the winter. It likely won't be harvested until spring and significant yield loss will occur.

Prior to this week's storm, as much as 25 inches of snow had already fallen in parts of the Dakotas—two states where the corn harvest was running way behind in December. Other states where the corn harvest is still not done are Nebraska, Michigan, Wisconsin, Illinois and a few areas of Iowa. In Iowa, a surprising number of fields in southeast and south central Iowa are yet to be harvested.

"We'll get a better handle on the situation when USDA publishes its annual crop production summary estimates for 2009," says Chad Hart, Iowa State University Extension grain marketing economist. That report will be released January 12, 2010. Normally, the January report is a yawner—as it fine-tunes the November USDA estimates but doesn't usually make any big changes in those estimates. That's because the crop is pretty much in the bin by Thanksgiving—usually. But this year, the January 2010 report will play the role that the November USDA report usually does--in giving an estimate of the crop size for 2009.

December 2009 was record-cold for December in Iowa

Iowans wish to forget what was a very cold last month of the year 2009. Deep snow received during the second week of December kept some corn fields from being harvested. However, Iowa farmers harvested a larger percentage of their corn crop than farmers in many other Midwest states. The below-average temperatures also delayed post-harvest field work which will most likely be completed in the spring. Livestock producers continue the winter struggles of keeping feed and water available for cattle in snow-covered pastures.

According to the weather and crop conditions survey, released January 4, 2010, by the Iowa office of USDA's National Ag Statistics Service, the average depth of snow cover for the month of December 2009 was 20 inches, well above December 2008's average of 10 inches.

For the month of December 2010 frost penetration averaged 11 inches compared to the previous December's 10 inches. Soil moisture availability is currently rated 2% short, 77% adequate and 21% surplus for Iowa. Grain movement in the state during December was 37% none, 44% light, 17% moderate and 2% heavy.

Quality of Iowa's hay supply down this winter—only 35% good

Availability of hay and roughage supplies was 12% short, 80% adequate and 8% surplus during December 2009. Quality of hay and roughage was 9% poor, 56% fair and 35% good. Use of stubble fields for grazing 52% none, 35% light, 12% moderate and 1% heavy.

Hog and pig losses in December were 4% below average, 92% average and 4% above average. Cattle and calf losses were 7% below average, 87% average and 6% above average.

Iowa preliminary weather summary for December 2009

Harry Hillaker, state climatologist for the Iowa Department of Ag, says December 2009 temperatures for Iowa averaged 19.8 degrees or 2.8 degrees below normal while precipitation totaled 2.70 inches or 1.47 inches above normal. This ranks as the 31st coolest and 2nd wettest December in 137 years of recordkeeping in the state. Only 1982 brought more December precipitation, with 3.43 inches.

* Temperatures. The very mild weather pattern of November continued briefly into December. Daytime highs on December 1, 2009 reached into the 50's and 60's statewide with Ankeny, Des Moines, Red Oak and Shenandoah the warmest at 62 degrees. However, only two of the next 16 days managed to reach normal.

The first single digit minimum temperatures of the season were recorded on the morning of December 4, 2009 with readings down to 2 degrees at Estherville and Swea City. This was followed by the first subzero readings on the morning of December 9 with minus 1 degree at Sibley. However, much colder weather wasn't far behind with Little Sioux falling to minus 19 degrees on the morning of December 10--when all but the far southeast corner of the state saw subzero readings.

Temperatures finally edged above normal from the 17th through the 25th with Burlington reaching 49 degrees early Christmas morning just prior to the arrival of another Arctic blast. Late month temperatures fell as low as to minus 18 degrees at Spencer on the morning of December 29.

* Heating degree day totals. Home heating requirements, as estimated by heating degree day totals, averaged 5% less in December 2009 than in December 2008 and 6% more than normal. Thus far this season (since July 1) heating requirements through the end of 2009 are running 3% less than last year (end of 2008) and 2% less than normal.

* Precipitation. December 2009 was an exceptionally wet and snowy month thanks to two very strong storm systems. The first event, coming mostly in the form of snow, began late on December 7, peaked on the 8th, and continued into the afternoon of the 9th. A statewide average of 0.80 inches of precipitation and 10.2 inches of snow fell in this storm. This was the largest snow event since the blizzard of January 2-4, 1971 (and this December 7-9, 2009 storm was the 3rd largest statewide storm total since 1950).

The heaviest snow in the December 2009 event fell from southwest, through central, and into northeast Iowa where amounts of 12 to 16 inches were common. Highest official totals were 16.2 inch totals at Corning and Osceola.

Wind gusts of 50 mph or greater were common over the northern two-thirds of Iowa on December 9 with a peak gust of 61 mph at Estherville. A second major storm slowly moved into Iowa on the morning of December 23 and finally exited the state on the 27th. This storm brought snow to all of Iowa, but also an unseasonably large amount of rain to eastern sections.

Statewide, the second storm brought an average of 1.55 inches of precipitation and 8.2 inches of snow (8th largest statewide storm total since 1950). Heaviest snow fell over northwest Iowa where Spencer recorded 24.0 inches of snow (new single storm record for Spencer, old record 19.0 inches February 17-18, 1962).

Spencer set new state record for snowfall in December 2009

Portions of west central and central Iowa also endured a period of freezing rain on December 23-24 with glazing of up to one-half inch. Winds speeds with this second blizzard were not as high as with the first storm with the higher winds being confined to far western Iowa where Sioux City recorded gusts to 51 mph.

Thanks in large part to these two major events, Spencer set a state record for maximum December snowfall with a total of 40.0 inches (old record 39.6 inches at Britt in December 2000). Record calendar month snowfalls included these three cities:

City           Dec. 2009         Old monthly record       

Spencer         40.0          39.0 in February 1962

Sioux City      34.0          29.1 in January 1982

Denison         31.0          26.5 in January 1932

Overall December 2009 statewide average snowfall was 23.3 inches for Iowa. Normal for December is only 7.3 inches. This is the second highest statewide average for any calendar month (behind only December 2000's 25.5 inch average). Despite the second-least snow of record in November the season-to-date statewide average snowfall through the end of December is also the second highest of record at 23.9 inches. Normal snowfall through the end of December is 11.2 inches while the record total for this period is 28.0 inches set in 2000.